Reish Luftman McDaniel & Reicher provides this article: Taking Stock: Managing the Risk of Company Stock. The article provides some good suggestions for minimizing ERISA fiduciary risk where a 401(k) offers company stock as a match and/or as an investment option.
(Note: The article does not discuss plan governance structure or procedural prudence which, in my opinion, are also very important in minimizing ERISA fiduciary liability.)